@ionic/core/dist/collection/components/tab/tab.js

Base components for Ionic

import { Build, Component, Element, Host, Method, Prop, Watch, h } from '@stencil/core';
import { attachComponent } from '../../utils/framework-delegate';
export class Tab {
  constructor() {
    this.loaded = false;
    /** @internal */
    this.active = false;
  }
  async componentWillLoad() {
    if (Build.isDev) {
      if (this.component !== undefined && this.el.childElementCount > 0) {
        console.error('You can not use a lazy-loaded component in a tab and inlined content at the same time.' +
          `- Remove the component attribute in: <ion-tab component="${this.component}">` +
          ` or` +
          `- Remove the embedded content inside the ion-tab: <ion-tab></ion-tab>`);
      }
    }
    if (this.active) {
      await this.setActive();
    }
  }
  /** Set the active component for the tab */
  async setActive() {
    await this.prepareLazyLoaded();
    this.active = true;
  }
  changeActive(isActive) {
    if (isActive) {
      this.prepareLazyLoaded();
    }
  }
  prepareLazyLoaded() {
    if (!this.loaded && this.component != null) {
      this.loaded = true;
      try {
        return attachComponent(this.delegate, this.el, this.component, ['ion-page']);
      }
      catch (e) {
        console.error(e);
      }
    }
    return Promise.resolve(undefined);
  }
  render() {
    const { tab, active, component } = this;
    return (h(Host, { role: "tabpanel", "aria-hidden": !active ? 'true' : null, "aria-labelledby": `tab-button-${tab}`, class: {
        'ion-page': component === undefined,
        'tab-hidden': !active
      } },
      h("slot", null)));
  }
  static get is() { return "ion-tab"; }
  static get encapsulation() { return "shadow"; }
  static get originalStyleUrls() { return {
    "$": ["tab.scss"]
  }; }
  static get styleUrls() { return {
    "$": ["tab.css"]
  }; }
  static get properties() { return {
    "active": {
      "type": "boolean",
      "mutable": true,
      "complexType": {
        "original": "boolean",
        "resolved": "boolean",
        "references": {}
      },
      "required": false,
      "optional": false,
      "docs": {
        "tags": [{
            "text": undefined,
            "name": "internal"
          }],
        "text": ""
      },
      "attribute": "active",
      "reflect": false,
      "defaultValue": "false"
    },
    "delegate": {
      "type": "unknown",
      "mutable": false,
      "complexType": {
        "original": "FrameworkDelegate",
        "resolved": "FrameworkDelegate | undefined",
        "references": {
          "FrameworkDelegate": {
            "location": "import",
            "path": "../../interface"
          }
        }
      },
      "required": false,
      "optional": true,
      "docs": {
        "tags": [{
            "text": undefined,
            "name": "internal"
          }],
        "text": ""
      }
    },
    "tab": {
      "type": "string",
      "mutable": false,
      "complexType": {
        "original": "string",
        "resolved": "string",
        "references": {}
      },
      "required": true,
      "optional": false,
      "docs": {
        "tags": [],
        "text": "A tab id must be provided for each `ion-tab`. It's used internally to reference\nthe selected tab or by the router to switch between them."
      },
      "attribute": "tab",
      "reflect": false
    },
    "component": {
      "type": "string",
      "mutable": false,
      "complexType": {
        "original": "ComponentRef",
        "resolved": "Function | HTMLElement | null | string | undefined",
        "references": {
          "ComponentRef": {
            "location": "import",
            "path": "../../interface"
          }
        }
      },
      "required": false,
      "optional": true,
      "docs": {
        "tags": [],
        "text": "The component to display inside of the tab."
      },
      "attribute": "component",
      "reflect": false
    }
  }; }
  static get methods() { return {
    "setActive": {
      "complexType": {
        "signature": "() => Promise<void>",
        "parameters": [],
        "references": {
          "Promise": {
            "location": "global"
          }
        },
        "return": "Promise<void>"
      },
      "docs": {
        "text": "Set the active component for the tab",
        "tags": []
      }
    }
  }; }
  static get elementRef() { return "el"; }
  static get watchers() { return [{
      "propName": "active",
      "methodName": "changeActive"
    }]; }
}